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DOE OSTI · 3375761

Probing boron vacancy defects in hBN via single spin relaxometry

Melendez, Alex L. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0009000316101340)·Gong, Ruotian [Washington University in St. Louis, MO (United States)] (ORCID:0009000661674326)·He, Guanghui [Washington University in St. Louis, MO (United States)] (ORCID:0009000973077694)·Wang, Yan [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000265456434)·Wu, Yueh-Chun [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000292996882)·Poirier, Thomas [Kansas State University, Manhattan, KS (United States)] (ORCID:0009000352589160)·Randolph, Steven [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000197074337)·Ghosh, Sujoy [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000328948971)·Liang, Liangbo [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000311990049)·Jesse, Stephen [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000211688483)·Li, An-Ping [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000344007493)·Damron, Joshua T. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000334090190)·Lawrie, Benjamin J. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:000000031431066X)·Edgar, James H. [Kansas State University, Manhattan, KS (United States)] (ORCID:0000000309185964)·Vlassiouk, Ivan V. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000254940386)·Zu, Chong [Washington University in St. Louis, MO (United States)] (ORCID:0000000178031315)·Zhao, Huan [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000249820865)
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Abstract

Spin defects in solids offer promising platforms for quantum sensing and memory due to their long coherence times and optical addressability. Here, we integrate a single nitrogen-vacancy (NV) center in diamond with scanning probe microscopy to detect, read out, and spatially map spin-based quantum sensors at the nanoscale. Using the boron vacancy ($V$$^{–}_{B}$) center in hexagonal boron nitride—an emerging two-dimensional spin system—as a model, we detect its electron spin resonance indirectly via changes in the spin relaxation time (T 1 ) of a nearby NV center, eliminating the need for optical excitation or fluorescence detection of the $V$$^{–}_{B}$. Cross-relaxation between NV and $V$$^{–}_{B}$ ensembles significantly reduces NV T1, enabling quantitative nanoscale mapping of defect densities beyond the optical diffraction limit and clear resolution of hyperfine splitting in isotopically enriched h 10 B 15 N. Our method demonstrates interactions between spin sensors in 3D and 2D materials, establishing NV centers as versatile probes for characterizing otherwise inaccessible spin defects.

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Melendez, Alex L. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0009000316101340), Gong, Ruotian [Washington University in St. Louis, MO (United States)] (ORCID:0009000661674326), He, Guanghui [Washington University in St. Louis, MO (United States)] (ORCID:0009000973077694), Wang, Yan [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000265456434), Wu, Yueh-Chun [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000292996882), Poirier, Thomas [Kansas State University, Manhattan, KS (United States)] (ORCID:0009000352589160), Randolph, Steven [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000197074337), Ghosh, Sujoy [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000328948971), Liang, Liangbo [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000311990049), Jesse, Stephen [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000211688483), Li, An-Ping [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000344007493), Damron, Joshua T. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000334090190), Lawrie, Benjamin J. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:000000031431066X), Edgar, James H. [Kansas State University, Manhattan, KS (United States)] (ORCID:0000000309185964), Vlassiouk, Ivan V. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000254940386), Zu, Chong [Washington University in St. Louis, MO (United States)] (ORCID:0000000178031315), Zhao, Huan [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)] (ORCID:0000000249820865). 2026-03-10. Probing boron vacancy defects in hBN via single spin relaxometry. https://doi.org/10.1038/s41467-026-70545-6

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